<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title></title>
    <style type="text/css">
       button{
           width: 200px;
           height: 50px;
           border-radius: 15px;
           border: none;
           animation: breath 2s linear infinite;
       }
    @keyframes breath {
        from{
            background-color: red;
            box-shadow: 2px 2px 2px gray,2px 2px 2px gray inset;
        }
        to{
            background-color: blue;
            box-shadow: 2px 2px 15px gray,2px 2px 15px gray inset;
        }
    }




    </style>
</head>
<body>
    <button>发光的按钮</button>
</body>
</html>